The present invention relates to a cleaning device in general, and more particularly to a cleaning device which includes at least one main brush and an additional brush which delivers dirt to the main brush from regions which are inaccessible to the main brush.
There are already known various cleaning devices of the type here under consideration which devices, in general, include a main brush which is mounted in a housing of the cleaning device for rotation about an axis which is parallel to the surface to be cleaned and extends transversely to the direction of movement of the cleaning device over the surface to be cleaned. In addition thereto, a pair of additional brushes is mounted in the corner regions, preferably front corner regions of the device when considered in the direction of movement thereof, which additional brushes rotate about axes which are substantially normal to the surface to be cleaned. Each such additional brush has an annulus of bristles which extend substantially radially of the axis of rotation of the additional brush and toward the surface to be cleaned.
The additional brushes of conventional cleaning devices are usually driven into rotation in opposite angular directions in response to the movement of the cleaning device in opposite directions over the surface to be cleaned. In order to assure that the additional brushes will pick up dirt from regions without the path of movement of the main brush and deposit it on the surface to be cleaned within such path, it has already been proposed to mount the additional brushes in the housing of the cleaning device for pivoting in response to the change of direction of movement of the cleaning device in the opposite directions so that diametrally opposite regions of the annulus of bristles will respectively come into contact with the surface to be cleaned and deliver the dirt from without to within the path of the main brush.
There is already known a conventional cleaning device of the type here under discussion in which the additional brushes are mounted in the housing of the cleaning device for pivoting between two end positions in one of which one portion of the annulus of bristles when considered with respect to the housing comes into contact with the surface to be cleaned when the cleaning device is moved in one of the opposite directions, while a diametrally opposite portion of the annulus of bristles when considered in relation to the housing comes into contact with the surface to be cleaned when the cleaning device is displaced in the other of the opposite directions. Inasmuch as the pivoting of the additional brush takes place simultaneously with the reversal of the direction of angular displacement thereof, the bristles of the additional brush will always move dirt in the same direction, that is, toward the main brush of the cleaning device. Thus, when the driving and pivoting mechanisms are properly selected, it is achieved that the additional brush is always in contact with the surface to be cleaned in a region of the annulus of bristles which conducts movement in direction toward the main brush and thus to the dirt-collecting receptacles which are arranged alongside the main brush so that the cleaning device effectively cleans the surface irrespective of the direction of movement of the cleaning device over such surface. In this prior-art device, the additional brush is mounted in a bearing body which is mounted in the housing of the cleaning device for pivoting about an axis which extends substantially normal to the direction of movement of the cleaning device over the surface to be cleaned and which is substantially parallel to the surface. The cleaning device of this construction includes a control mechanism which pivots the bearing body relative to the housing of the cleaning device between the above-mentioned end positions in which the respective diametrally opposite portions of the annulus of bristles come into contact with the surface to be cleaned.
Experience with this type of prior-art cleaning device has shown that such device is rather complex and, consequently, expensive, particularly inasmuch as the additional brush is mounted in a separate bearing body which, in turn, is mounted in the housing of the cleaning device for pivoting between the end positions thereof. The multitude of parts which are needed for mounting the cleaning body or brush in the housing of the cleaning device contributes considerably to the complex and expensive manufacture and assembly of the prior art cleaning device of this type.